Disturbances in Water Balance Controls Following Lesions to the Area Postrema and Adjacent Solitary Nucleus

Abstract

Lesions which remove the area postrema (AP) and the subjacent portions of the nucleus of the solitary tract (cmNTS) which lie in the caudal brainstem close to the dorsal spinomedullary junction cause dramatic and apparently permanent alterations in energy and fluid balance1,2. There is a well characterized syndrome of transient hypophagia and accompanying weight loss. Two to three weeks into this syndrome normophagia resumes with eventual stabilization of body weight but at a lower level. In addition there is a mild hyperdipsia. See figure 1.